Re: [PATCH 04/13] mm: Fix pmd_read_atomic()

[Peter Zijlstra]

On Sat, Oct 22, 2022 at 10:30:51AM -0700, Linus Torvalds wrote:
> On Sat, Oct 22, 2022 at 4:48 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > --- a/include/linux/pgtable.h
> > +++ b/include/linux/pgtable.h
> > @@ -258,6 +258,13 @@ static inline pte_t ptep_get(pte_t *ptep
> >  }
> >  #endif
> >
> > +#ifndef __HAVE_ARCH_PMDP_GET
> > +static inline pmd_t pmdp_get(pmd_t *pmdp)
> > +{
> > +       return READ_ONCE(*pmdp);
> > +}
> > +#endif
> 
> What, what, what?
> 
> Where did that __HAVE_ARCH_PMDP_GET come from?

Copy/paste like from ptep_get(), that has __HAVE_ARCH_PTEP_GET (which
does appear to get used, once).

Do I break the pattern and simply leave this off, or do I stay
consistent even though we hate it a little? ;-)